. Handbook of flower pollination : based upon Hermann Mu?ller's work 'The fertilisation of flowers by insects' . Fertilization of plants. 208 A NGIOSPERMAE—DICO TYLEDONES Herm. Miiller calls attention ('Fertilisation,' p. 14) to a peculiarity of the flowers of this species, i. e. that they are not adequately protected against nectar-thieves. In the afternoon, when the flowers begin to close, the honey-bee frequently thrusts its proboscis between the five sepals of blossoms which are still fresh though shut, and thus empties the nectar receptacle from outside. On some few occasions Miiller even
. Handbook of flower pollination : based upon Hermann Mu?ller's work 'The fertilisation of flowers by insects' . Fertilization of plants. 208 A NGIOSPERMAE—DICO TYLEDONES Herm. Miiller calls attention ('Fertilisation,' p. 14) to a peculiarity of the flowers of this species, i. e. that they are not adequately protected against nectar-thieves. In the afternoon, when the flowers begin to close, the honey-bee frequently thrusts its proboscis between the five sepals of blossoms which are still fresh though shut, and thus empties the nectar receptacle from outside. On some few occasions Miiller even observed bees which had rifled several such flowers in this way, continuing their depredations on neighbouring ones that were still open. 517. M. rotundifolia L. ( = M. borealis Wallm). (Herm. Miiller, ' Fertilisation,' pp. 142-4, ' Weit. Beob.,' II, p. 221: Warnstorf, Verh. bot. Ver., Berlin, xxxvii, 1895.)—The flower mechanism of this species at the beginning of anthesis is the same as that of the last one. But, in correlation with its much smaller and less brightly coloured flowers, M. rotundifolia is capable of automatic self-polHnation, which is necessary for the maintenance of the species since the number of visitors is naturally much smaller. The stamens remain so far erect that the pollen-covered anthers are touched by the recurved stigmatic branches (see Fig. 60).. Fig. 62. Malva sylvestris, L.^ and M. rotundifolia, L. (after Herm. Miiller). M. sylvcstris: (i) Column of stamens in the buH, enclosing; the styles. {2) Sexual organs in the 6rst (male) stage. (3) The same in the transition from the first to the second stage. (4) The same in the second (female) (5) M. rotundifolia in the last stage, showing self-pollination, a, anthers ; j/, stigmas. Warnstorf gives a somewhat different account, as follows.—Most of the German species of Malva, such as M. Alcea, M. sylvestris, and M. neglecta, possess strongly protandrous flowers, so that self-pollination appears to b
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